Super-enhanced, adjustably buoyant floating island

ABSTRACT

A floating island comprising one or more layers of nonwoven mesh material and optional buoyant nodules. The mesh material is optionally coated with a spray-on elastomer or inoculated with nutrients or microorganisms. The island can include buoyant growth medium, floats, buoyant blocks, a prefabricated seed blanket, a dunking feature, capillary tubes, wicking units and/or bell flotation units. A larger embodiment is comprised of nonwoven mesh material, buoyant nodules, supplemental flotation units, stepping pads and optional load distribution members. Other optional features include a stepping stone flotation assembly, a stepping stone/vertical buoyant member flotation assembly, and a floating log assembly. The buoyancy of the island can be adjusted with a rigid framework of horizontal members, vertical members that can be moved vertically within the island, and/or a framework of prefabricated flotation tubes and cross members. The present invention also covers a floating island with a boat docking location.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.11/569,941 filed on Nov. 21, 2006.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a super-enhanced, adjustably buoyantfloating island that can be deployed in ponds, lakes, rivers or anyother body of water to monitor, regulate and improve water quality,enhance plant and animal life, and complement the natural surroundings.

2. Description of the Related Art

In bodies of water such as ponds and lakes, algae growth and the naturalprocess of eutrophication can lead to an increase in land mass andcorresponding decrease in water volume, the killing of fish and otherorganisms, and the diminishment of aesthetic appearance. Variousfloating mechanisms have been devised with the aim of purifying water,cultivating plants, dispensing fertilizer, or counteracting the effectsof eutrophication. None of these inventions anticipates the combinationof features provided by the present invention.

U.S. Pat. No. 5,799,440 (Ishikawa et al., 1998) discloses a floatingisland comprising: (i) a planter with holes in it to allow the roots ofthe plants to grow into the water and to supply water to the soil in theplanter; and (ii) an oxygen-generating agent container attached to thebottom of the planter. The planter is made of a foamed resin with areinforcing film of polyurethane elastomer on the surface. The inventionalso includes: (i) a layer of porous material on the inner surface ofthe bottom of the planter that has an aerobic microorganism immobilizedin it; and (ii) a plant cultivation bag to hold the soil. In thepreferred embodiment, the oxygen-generating agent is calcium peroxide,and the soil in the planter is covered with a net or fabric that ispermeable to water and air and is not harmful to the plants. In additionto generating oxygen, calcium peroxide also eliminates phosphorus,thereby restricting algae growth.

U.S. Pat. No. 4,086,161 (Burton, 1978) sets forth an ecological systemand method for counteracting the effects of eutrophication in bodies ofwater such as marshlands, inland ponds and lakes. The system usesclusters of bark fibers positioned in the upper, relatively oxygen-richzones of such bodies of water. These bark clusters attract and holdexcessive nutrient deposition in the form of colloidal wastes andaquatic algae and also provide a safe habitat for algae predators andfeeders.

U.S. Pat. No. 6,086,755 (Tepper, 2000) provides a floating hydroponicbiofiltration device for use in a body of water containing plant-eatingfish. The invention includes a float, a mesh and a matting. The floatcontains an aperture devoid of soil in which a terrestrial plant isinserted. The mesh is at a substantial depth below the float and servesto enable passage of oxygenated water to the plant roots while excludinglarge plant-eating fish. The mesh also serves as a substrate surface forthe growth of nitrogen-converting bacteria, which convert the ammonia offish waste to nitrates useful to plants. The matting anchors the plantroots and partially excludes plant-eating fish from a portion of theplant roots. In the preferred embodiment, the mesh and matting areformed of plastic.

U.S. Pat. Nos. 5,766,474 (Smith et al., 1998) and 5,528,856 (Smith etal., 1996) set forth a biomass impoundment management system that usessunlight to purify water. The main purpose of this invention is tocontrol impurities in water impoundments, such as ammonia, nitrogen,phosphorous and heavy metals. It is well known that nitrogen andphosphorous are a primary food source for various undesirable algaespecies, and ammonia and heavy metals are toxic to humans, fish andother organisms. This invention aims to purify water by allowing rootedbottom dwelling plants to grow and remain healthy on the bottom of awater impoundment while allowing rootless floating plants to grow andremain healthy above them. The non-rooted, floating plants are containedin a large surface area provided by elongated channels, which areoriented in a North-South direction to take full advantage of the sun.The elongated channels are designed to take advantage of wave activityto increase productivity.

U.S. Pat. No. 5,337,516 (Hondulas, 1994) sets forth an apparatus fortreating waste water that includes a waste water basin and a number ofwetland plants in floating containers. The idea underlying thisinvention is that the root systems of the wetland plants will treat thewaste water. The extent of growth of the root systems is controlled byan adjustable platform associated with each floating container, so thatthe aerobic and anaerobic zones within the waste water basin arecontrolled and can be adjusted or varied as required. Similarly, U.S.Pat. No. 5,106,504 (Murray, 1992) covers an artificial water impoundmentsystem designed to remove biologically fixable pollutants from urban orindustrial waste water using aquatic plants to absorb pollutants.

U.S. Pat. No. 4,536,988 (Hogen, 1985) relates to a floating containmentbarrier grid structure for the containment of floating aquatic plants ina body of water. This invention is designed to facilitate the commercialcultivation and harvesting of aquatic plants. The grid structureconsists of elongated flexible sheets that are interconnected at spacedintervals along their longitudinal axes to form a plurality of barriersections in a web-like arrangement. Through the use of an anchoringmeans, the barrier grid is tensioned so that certain portions of thestructure are submerged beneath the surface of the water by a devicethat harvests the floating aquatic plants.

U.S. Pat. Nos. 4,037,360 (Farnsworth, 1977) and 3,927,491 (Farnsworth,1975) disclose a raft apparatus for growing plants by means of waterculture or hydroponics. The raft floats on a nutrient solution, andbuoyancy of the rafts is increased during plant growth by placing asmall raft on a larger raft or on auxiliary buoyancy means. U.S. Pat.No. 5,261,185 (Kolde et al., 1973) also involves an apparatus floatingon a nutrient solution. In this invention, rafts are floated in a waterculture tank filled with nutrient solution, plant containers areinserted in vertically oriented channels in the raft, and the plants arecultivated by gradually moving the raft from one end of the waterculture tank to another.

U.S. Pat. No. 4,487,588 (Lewis, III et al., 1984) addresses asubmersible raft for the cultivation of plant life such as endangeredsea grasses. The raft is manufactured from standard polyvinyl chloridetubing and fittings.

U.S. Pat. No. 6,014,838 (Asher, 2000) discloses a simple floatable unitfor decorative vegetation. U.S. Pat. No. 5,836,108 (Scheuer, 1998)describes a floating planter box comprising a polyhedral planar basemember of a synthetic foam resin less dense than water and an optionalanchoring means.

U.S. Pat. Nos. 5,312,601 (Patrick, 1994) and 5,143,020 (Patrick, 1992)involve a simple apparatus for dispensing fertilizer in a pond. Theinvention consists of a flotation structure surrounded by a porousmaterial such as a net sack and an opening in the flotation structurethrough which fertilizer is dumped. The fertilizer is dissolved by waterflowing through the net sack at the bottom of the flotation structure.

U.S. Patent Application Pub. No. US 2003/0208954 (Bulk) relates to afloating planter for plants and fish. The planter is made of closed cellplastic foam and includes recesses for above-water pot holders and afloating underside support for oxygenating underwater plants. The islandhas passageways downward through the island structure that open into thewater and allow plant roots to reach the water. The island also hascavities that function as shelter for amphibious creatures such asfrogs.

In addition to the patents and patent application discussed above, thereare a number of patents and at least one published patent applicationthat deal with growth medium for plants. For example, U.S. Pat. No.5,207,733 (Perrin, 1993) involves the use of a low-density, rigid,unicellular (i.e., closed cell) expanded polyurethane foam that isperforated to facilitate the passage of emergent plant roots and toprovide voids for water absorption and retention.

U.S. Pat. No. 2,639,549 (Wubben et al., 1953) describes a hydroponicgrowth medium that comprises a gravel bed that rests on a perforatedbottom, which in turn rests on top of a ridged ground plate. A pump andgutters are used to circulate a nutrient solution throughout the gravelbed.

U.S. Pat. No. 5,224,292 (Anton, 1993) discloses a growth medium thatconsists of a layer of hollow nonwoven polyester fibers, wherein thelumens (or hollow insides) of the fibers contain a plant adjuvant (orsomething that assists plant growth), such as plant nutrients,fungicides, algaecides, weed killers and pesticides.

U.S. Pat. No. 6,615,539 (Obonai et al., 2003) provides a water-retainingsupport comprised of a hydrogel-forming polymer that is used as a plantgrowth medium. The object of the Obonai invention was to provide ahydrogel that would retain water without inhibiting plant root growth.

U.S. Patent Application Pub. No. US 2003/0051398 (Kosinski) involves asoil substitute that consists of fiberballs made of a biodegradablepolymer fiber (for example, polyester) with a specific cut length andaverage dimension. The patent application includes a claim for a methodof supporting plant growth by contacting plant material with thefiberball growth medium.

BRIEF SUMMARY OF THE INVENTION

The present invention covers several different embodiments of a floatingisland comprising one or more layers of nonwoven mesh material. Thepresent invention can be deployed in ponds, lakes, rivers or any otherbody of water to improve water quality, enhance plant and animal life,and complement the natural surroundings. Larger embodiments of thepresent invention may help prevent the greenhouse effect through carbonsequestration, which involves the removal of carbon dioxide from theatmosphere and the conversion of carbon to biomass. The largerembodiments of the present invention may also be used for farming oreven habitation on or in bodies of water.

The nonwoven mesh material of the present invention can be coated with aspray-on elastomer, inoculated with nutrients, or inoculated withaerobic or anaerobic microorganisms. The floating island can alsocomprise buoyant nodules that are manufactured into the mesh material orintegrated into the mesh material during assembly. The layers of meshmaterial can be joined together by an adhesive, and holes can be formedinto the top layer or layers for plants or flotation materials. Theisland can include floats, buoyant blocks, a dunking feature, capillarytubes and/or wicking units. It can also include a top cover that isoptionally biodegradable and that protects seeds that are eitherintegrated into the top cover or placed underneath it.

In an alternate embodiment, the floating island includes bell flotationunits comprising an air compressor, tubing, a solenoid valve, a controlwire and one or more bells. The bells can be formed of thermoplastic,closed cell foamed metal, amorphous metal, cement or plastic.

The present invention also includes a larger embodiment that can bearthe weight of one or more people. This larger embodiment is comprised ofat least one layer of nonwoven mesh material, buoyant nodules,supplemental flotation units and stepping pads. This embodimentoptionally includes one or more load distribution members or anadjustably buoyant framework comprising prefabricated flotation tubesand cross members. Other optional features include a stepping stoneflotation assembly, a stepping stone/vertical buoyant member flotationassembly, and a floating log assembly. The buoyancy of the island can beadjusted with a rigid framework that comprises one or more horizontalmembers and, optionally, a water tube, an air control valve, and an airtube. The island can also include upper and lower vertical members thatcan be moved vertically within the island to further adjust itsbuoyancy.

The present invention also covers a floating island with a boat dockinglocation that is shaped so that the docked boat is mostly surrounded byisland material. Low abrasion padding can be placed around the innerperimeter of the boat docking location to provide extra protection forthe boat hull.

Any of the embodiments of the present invention can be supplemented withadditional island modules that are comprised of a single layer ofnonwoven mesh material impregnated with buoyant material.

The present invention also includes a prefabricated seed blanket thatcan be used to seed the island. It also includes a bonded growth mediumfor use in connection with the floating island of the present inventionand several methods of manufacturing a floating island with the bondedgrowth medium of the present invention.

The present invention encompasses a method of attaching various layersof nonwoven mesh material, a method of forming holes in the nonwovenmesh material, and a method of fabricating a floating island from scrappieces of nonwoven mesh material. It also includes a method ofconstructing floating islands by creating multiple island cutouts fromthe nonwoven mesh material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the nonwoven mesh embodiment of the presentinvention.

FIG. 2 is a section view of FIG. 1 taken at A-A showing a firstembodiment of the nonwoven mesh island.

FIG. 3 is a section view of FIG. 1 taken at A-A showing a secondembodiment of the nonwoven mesh island.

FIG. 4 is a section view of FIG. 1 taken at A-A showing a thirdembodiment of the nonwoven mesh island.

FIG. 5 is a section view of FIG. 1 taken at A-A showing a fourthembodiment of the nonwoven mesh island.

FIG. 6 is a side view of a landscaping pin and a partial section view ofa multi-layered island showing a method of attaching the layers with amodified landscaping pin.

FIG. 7 is a side view of an apparatus used for opening holes intononwoven mesh material without cutting or melting the mesh fibers.

FIG. 8 is a schematic illustration of a floating island fabricated fromscrap pieces of nonwoven mesh material.

FIG. 9 is a side view of a floating island designed to provide securityand feeding habitat for small fish.

FIG. 10 is a side view of an alternative embodiment of a floating islandthat uses nonwoven mesh as a protective barrier for small fish.

FIG. 11 is a section view of the island illustrating an optional dunkingfeature.

FIG. 12 is a section view of the island with optional “capillary action”features.

FIG. 13 is a section view of the island with optional “wicking action”features.

FIG. 14 is a first section view of an embodiment of the presentinvention with optional flotation “bells.”

FIG. 15 is a second section view of an embodiment of the presentinvention with optional flotation “bells” in a high-buoyancy position.

FIG. 16 is a side section view of a prefabricated seed blanket.

FIG. 17 is a section view of a first alternative embodiment of afloating island designed to support the weight of one or more persons.

FIG. 18 is a section view of a second alternative embodiment of afloating island designed to support the weight of one or more persons.

FIG. 19 is a top view of an artificial stepping stone and an artificialtree log.

FIG. 20 is a section view of a floating island with stepping stones,artificial logs, and means for providing additional buoyancy.

FIG. 21 is a perspective view of the framework for a floating islandcontaining both horizontal and vertical members.

FIG. 22 is a perspective view of an alternative embodiment of the islandframework, in which the horizontal members are comprised of a perforatedpipe and an inflatable bag.

FIG. 23 is a perspective view of an adjustably buoyant flotationframework that is comprised of prefabricated sections.

FIG. 24 is a section view of an embodiment of the present invention thatincludes single attachment point flotation units.

FIG. 25 is a section view of an embodiment of the present invention thatincludes a dual-ring buoy attached to the island with landscaping pins.

FIG. 26 is a section view of an embodiment of the present invention thatincludes receiver units.

FIG. 27 is a section view of an energy-absorbing and wave-dampingfloating structure made from nonwoven mesh material.

FIG. 28 shows a group of identical, mass-produced floating islands (madeof nonwoven mesh material) that are connected to form a single island.

FIG. 29 shows a series of islands produced by the multiple concentriccutout method.

FIG. 30 shows a perspective view of a skeleton frame island created byusing the multiple concentric cutout method.

FIG. 31 shows a section view of skeleton frame island taken at line B-Bof FIG. 30.

FIG. 32 shows two alternative embodiments for installing plants and soilgrowth medium into a skeleton frame island.

FIG. 33 is a top view of a floating island with bonded growth medium,shown prior to plant growth.

FIG. 34 is a section view of the first embodiment of the bonded growthmedium taken at section C-C of FIG. 31, in which the bonded growthmedium is attached to the outer surface of the floating island.

FIG. 35 is a partial magnified view of FIG. 34, showing the variouscomponents of the bonded growth medium.

FIG. 36 is a section view of a floating island comprised of individuallayers of nonwoven mesh material that have been stacked and bondedtogether.

FIG. 37 is a magnified view of a portion of FIG. 34, showing thecomponents of the embedded bonded growth medium.

FIG. 38 is a side section view shown in schematic form of a waterdistribution system mounted on a floating island.

FIG. 39 is a top view of the water distribution system shown in FIG. 38.

FIG. 40 is a section view of a floating island optimized for use as abiotreatment system.

FIG. 41 is a top view of a floating island with an integral boat dockingarea.

FIG. 42 is a top view of an anchor that is designed to hold a floatingisland regardless of wind direction.

REFERENCE NUMBERS

-   1 Top layer (nonwoven mesh embodiment)-   2 Middle layer (nonwoven mesh embodiment)-   3 Bottom layer (nonwoven mesh embodiment)-   4 Nonwoven mesh material-   5 Buoyant nodules (nonwoven mesh embodiment)-   5 Cut holes-   7 Potted plant units-   8 Adhesive-   9 Floats-   10 Foam sealant-   11 Buoyant blocks-   12 Landscaping pin-   13 Bent end section of landscaping pin-   14 Steel spike-   15 Head end of steel spike-   16 Lower end of steel spike-   17 Electric or compressed air drill-   18 Mandrel-   19 Scrap pieces of mesh material-   20 Outer covering-   21 Tightly packed nonwoven mesh-   22 Loosely packed nonwoven mesh-   23 Small fish or baitfish-   24 Large predator fish-   25 Buoyant spacers-   26 Water pockets-   27 Flexible line-   28 Pulley-   29 Anchor block-   30 Island (dunking embodiment)-   31 Capillary tubes-   32 Absorbent top cover-   33 Plants growing above waterline-   34 Wicking units-   35 Floating island (“bell” embodiment)-   36 Compressor-   37 Tubing-   38 Solenoid valve-   39 Control wire-   40 Bell (flotation)-   41 Internal space-   42 Pond water level-   43 Seed blanket-   44 Lower seed-containment layer-   45 Middle composite seed layer-   46 Upper seed-containment layer-   47 Aquatic plant seeds-   48 Binder-   49 Supplemental flotation unit-   50 Stepping pad-   51 Load distribution member-   52 Artificial stepping stone-   53 Artificial tree limb-   54 Stepping stone flotation assembly-   55 Lower stepping stone-   56 Upper stepping stone-   57 Connecting cable unit-   58 Island body (generic)-   59 Stepping stone/vertical buoyant member assembly-   60 Vertical buoyant member-   61 Floating tree limb assembly-   62 Lower artificial tree limb-   63 Upper artificial tree limb-   64 Variable buoyancy, rigid framework-   65 Horizontal members-   66 Water tube-   67 Air control valve-   68 Air tube-   69 Perforated pipe-   70 Inflatable bag-   71 Holes in perforated pipe-   72 Lower vertical member-   73 Upper vertical member-   74 Watertight cap-   75 Collar-   76 Locking pin-   77 Locking pin holes-   78 Locking straps-   79 Wheel-   80 Skid-   81 Prefabricated flotation tube-   82 Prefabricated cross members-   83 Protective pipe-   84 Strap-   85 Pipe positioning device-   86 Attachment post-   87 Flotation unit (single attachment point)-   88 Barbed attachment spike-   89 Float (single attachment point flotation unit embodiment)-   90 Buoyant feature-   91 Retaining pin-   92 Dual-ring buoy-   93 Snap-on connector-   94 Fully penetrating receiver unit-   95 Pipe (receiver unit)-   96 Lower flange-   97 Upper flange-   98 Partially penetrating receiver unit-   99 Protective floating structure-   100 Shoreline-   101 Waves-   102 Identical mass-produced islands-   103 Connectors (modular island)-   104 Modular island structure-   105 First island in multiple cutout design.-   106 Second island in multiple cutout design-   107 Central opening within first island-   108 Third island in multiple cutout design-   109 Central opening within second island-   110 Skeleton frame island-   111 Skeleton frame-   112 Floor-   113 Divider-   114 Buoyant intrusions (skeleton island)-   115 Soil growth medium-   116 Soil-based plants-   117 Matrix-based plants-   118 Natural organic material-   119 Synthetic organic material-   120 First growth compartment-   121 Second growth compartment-   122 Prefabricated planter unit-   123 Shell (prefabricated planter unit)-   124 Island comprising bonded growth medium-   125 Bonded growth medium-   126 Porous matrix (bonded growth medium embodiment)-   127 Buoyant inclusions (bonded growth medium embodiment)-   128 Capillary channels (bonded growth medium embodiment)-   129 Peat fibers (or similar material)-   130 Binder-   131 Embedded seeds-   132 Topcoat seeds-   133 Nutrient particles-   134 Buoyant pellets-   135 Infiltration zone-   136 Floating island with pumped water distribution system-   137 Water distribution system-   138 Water pump-   139 Distribution pipes-   140 Nonwoven mesh island body (pumped filtration embodiment)-   141 Aquatic plants selected for nutrient uptake-   142 Enclosure tray-   143 Air bubbles-   144 Perforations (tray)-   145 Floating island (boat docking embodiment)-   147 Low-abrasion padding-   148 Anchor optimized for multiple wind directions-   149 Barb (anchor)-   150 Ring attachment point (anchor)

DETAILED DESCRIPTION OF THE INVENTION

The present invention is superior to any existing floating island-typetechnology because it provides a super-enhanced habitat for plants,improves water quality, discourages algae populations, slows the processof eutrophication, provides a habitat for fish and small animals, and isdesigned to be aesthetically pleasing. It is distinguishable from any ofthe patents reviewed above because it is designed to enhance theexisting natural plant and animal habitat. Installation of the presentinvention does not require the draining of water, construction of asubmerged substructure, fitting or alteration of a pond liner, ordisturbance of existing flora or fauna. By virtue of its design, thepresent invention results in only minimal water displacement, whichallows the pond or other water body to retain its carrying capacity anddoes not adversely affect the health of the water body.

In a natural floating island, the roots of living plants are supportedin a substrate composed mainly of other living roots, dead roots, andpartially decomposed organic materials derived from dead plants andmicrobes. This natural substrate is mimicked by the island matrix of thepresent invention, whose rigid structure and porosity provide an idealenvironment for the establishment of growing roots.

In a natural floating island, microbial gas production provides acontribution to island buoyancy. In the present invention, the matrixfibers (nonwoven mesh) provide a large surface area for naturallyoccurring and introduced microbes that convert pond nutrients intogasses that provide buoyancy.

In a natural floating island, the plants that have adapted successfullyfor island life generally provide their own buoyancy. For example, afifty-foot tall larch tree can survive on a natural floating islandbecause the buoyancy of the island in the vicinity of the tree issufficient to support the weight of the tree; while a short distanceaway, the buoyancy of the island is only adequate to support the weightof two-foot tall leatherleaf plants. In each case, the plant roots andthe biological community surrounding the roots provide adequate buoyancyto support the weight that is imposed by the above-water portion of theplant. Plants that cannot support their own weight are generally sparseon natural floating islands. In the present invention, plants with knownself-generating buoyancy can be selected for use on islands wherelong-term, self-sustaining buoyancy is required.

In a preferred embodiment of the present invention, the floating islandis comprised of a nonwoven mesh material. This embodiment is shown inFIGS. 1-5. The island shape in FIGS. 1-5 is shown to be elliptical inplan view, but in fact can take any regular or freeform shape. In any ofthe nonwoven mesh embodiments, the mesh material can be coated with a“soft-touch coating” comprised of a spray-on elastomer such as latex orpolyurethane. The purpose of the coating is to provide a less abrasiveor non-abrasive finish, and it can be applied in varying thicknessdepending upon the effect desired.

FIG. 1 is a top view of the nonwoven mesh embodiment of the presentinvention, which comprises a top layer 1, a middle layer 2, and a bottomlayer 3. FIG. 2 is a section view of FIG. 1 taken at A-A showing a firstembodiment of the nonwoven mesh island. Each of the layers 1, 2, 3 iscomprised of water-permeable, nonwoven mesh material 4 (such as POLY-FLOfilter material) that has buoyant nodules 5 manufactured into the mesh.The buoyant nodules 5 may be comprised of any suitable low-densitymaterial, such as closed cell polymer foam, polystyrene, cork, or hollowplastic balls. Holes 6 are cut into the top layer 1 and middle layer 2,and a potted plant unit 7 is installed in each hole. The layers arejoined together with adhesive 8. The adhesive 8 may be any suitablematerial, such as hot-melt glue or polyurethane foam sealant (such asDow Chemical's GREAT STUFF or FROTH-PAC foam sealant). The foam mayalternately be comprised of organic material, for example, soy-basedfoam, as described in the Journal of American Oil Chemists' Society,Vol. 76, No. 10 (October 1999). The foam sealant provides buoyancy,adhesion and rigidity to the structure. The buoyancy of the island canbe adjusted after installation by adding additional foam as required.

FIG. 3 is a section view of FIG. 1 taken at A-A showing a secondembodiment of the nonwoven mesh island. This embodiment is comprised ofmultiple layers of nonwoven polyester mesh, similar to what is shown inFIG. 2, except that flotation for this second embodiment is provided byfloats 9 that are installed into the embodiment during assembly of thelayers. The floats 9 may be made of any suitable material, such as hardplastic or plastic foam fish net floats.

FIG. 4 is a section view of FIG. 1 taken at A-A showing a thirdembodiment of the nonwoven mesh island. This embodiment is comprised ofmultiple layers of nonwoven polyester mesh, similar to what is shown inFIG. 2, except that flotation for the third embodiment is provided byexpanding foam sealant 10 (such as Dow Chemical's GREAT STUFF orFROTH-PAC foam sealant). The foam sealant 10 is injected as apressurized liquid into and through the fibers of the nonwoven meshmaterial 4. In addition to providing flotation, the foam sealant 10 alsobonds the layers together.

FIG. 5 is a section view of FIG. 1 taken at A-A showing a fourthembodiment of the nonwoven mesh island. This embodiment is comprised ofmultiple layers of nonwoven polyester mesh, similar to what is shown inFIG. 2, except that flotation for the fourth embodiment is provided bybuoyant blocks 11. The buoyant blocks 11 are inserted into holes (notshown) that are cut through the layers of nonwoven material. The buoyantblocks 11 may be retained within the holes by a friction-tight fit, andthey may be manually adjusted in the vertical direction (as indicated bythe arrows). This feature is particularly useful for adjusting thebuoyancy of the island to compensate for the changing weight of growingplants. Both the floats of FIG. 3 and the buoyant blocks of FIG. 5 maybe optionally perforated to provide additional pathways for plant roots.

In FIG. 1, the island is shown as being comprised of three layers. Inpractice, the present invention may be comprised of a single layer orany number of multiple layers. FIG. 6 illustrates a method of attachingthe layers of nonwoven mesh. In FIG. 6, a standard landscaping pin 12 ispushed through a top layer 1, a middle layer 2, and a bottom layer 3.The end sections 13 of the pin 12 are then bent upwards into U-shapes asshown and allowed to penetrate the bottom layer 3 in a second locationas shown. In this configuration, the landscaping pin 12 locks the layerstogether. One example of a commercially available landscaping pin is theeight-inch wire staple sold by North American Green of Evansville, Ind.

With respect to the embodiments shown in FIGS. 1-5, apertures forcontaining plants or flotation materials may optionally be cut, meltedor otherwise formed into the mesh material during manufacture. Apreferred method of forming apertures in the nonwoven mesh material isillustrated in FIG. 7. In this figure, a hole-opening tool is fashionedfrom a steel spike 14 by cutting the head 15 off the spike 14. The lowersection 16 of the spike is then inserted into a standard electric orair-powered drill 17. The lower section 16 is round in cross section,with a pyramid or cone-shaped end. The apparatus comprised of the drill17 and lower section 16 is used to open holes into layers of nonwovenmesh by pushing the lower section 16 through the nonwoven mesh whilerotating lower section 16 with the drill 17. The resulting cylindricallyshaped holes can be used to inject adhesive foam or to install plantsand seeds. If desired, a hole can be kept open by temporarily insertinganother steel spike 14 into the hole, until the adhesive, plant, or seedis installed.

This method of producing an opening in the mesh is superior to cutting ahole because it requires much less effort, is faster, and produces atemporary hole that contracts around any installed adhesive, plant, orseed. This method is superior to melting a hole because it does notproduce noxious fumes. An example of a suitable steel spike is ⅜-inch indiameter and 12 inches in length, available from McMaster-Carr (partnumber 97033A320). Larger diameter holes may be opened by substituting acustom manufactured mandrel 18 for the lower section 16. Such largerholes may be useful for installing rooted plants.

All of the embodiments depicted in FIGS. 1-5 share the same advantage interms of biological filtration. The nonwoven mesh material acts as abiological filter media in that it provides an ideal substrate forbacterial colonization and allows the free passage of water through themedia. The bacteria form beneficial biofilms and enhance the removal ofnitrate, phosphorous and other undesirable nutrients as the pond waterpasses through the media. This microbial bio-removal of nutrients, alongwith nutrient uptake by plants growing on the island, providessignificant nutrient removal from pond water and thereby improvesoverall pond health. As the microbes utilize nutrients and multiply,some of these microbes become detached from the island matrix and aredispersed throughout the pond, where they continue to remove nutrients.By this dispersal means, the island acts as microbial “seed source” toprovide nutrient-removal microbes throughout the pond. The rate ofnutrient removal is dependent upon the flow rate or hydraulic loadingthat the floating island experiences. The pond water could be pumped andsprayed over the island, which would increase the mass removal rate forpond water nutrients (including the possibility for actually filteringout algae). The island could be inoculated with aerobic or anaerobicmicroorganisms, plus start-up nutrients, in order to provide forenhanced nutrient uptake from the pond. A wind-powered, wave-powered orsolar-powered pump or similar mechanism could be added to increase therate of water flow through the filter media. All of the above wouldenhance the performance of the island as a floating biofilter.Additional embodiments that take advantage of these unique capabilitiesof the nonwoven mesh material of the present invention are describedbelow.

FIG. 8 shows a floating island comprised of scrap pieces of nonwovenmesh material 19, buoyant nodules 5, and an outer covering 20. The outercovering 20 may be fabricated by placing a bundle of mesh pieces 19 intoa heatable mold (not shown). When the mold is heated to the meltingpoint of the nonwoven mesh material (e.g., approximately 400° F. forpolyester), the outer fibers of the bundle soften and fuse, forming aporous “skin” around the unmelted center pieces of mesh material. Theskin forms an outer covering 20 that confines the pieces of meshmaterial 19, while allowing water, plant stems, and plant roots topenetrate. In an alternative method, the outer fibers of the bundle aresoftened and fused by applying a suitable solvent (e.g., di-octylphosphate is a solvent for polyvinyl chloride mesh). Alternately, bothheat and solvents may be simultaneously applied to form an outer skin onthe bundle of mesh material. The outer covering 20 may also be comprisedof a separate material, such as nylon netting.

FIG. 9 shows a floating island comprised of an upper section ofrelatively tightly packed nonwoven mesh 21 and a lower section ofrelatively loosely packed nonwoven mesh 22. The packing densities ofmeshes 21 and 22 are established during the manufacturing process ofthese materials. The packing density of the upper mesh 21 is selected soas to optimize it for plant root growth and durability. The packingdensity of the lower mesh 22 is selected so as to provide openingsbetween the mesh fibers that offer security and feeding habitat forsmall baitfish 23, while excluding larger predator fish 24. One exampleof small baitfish 23 is fathead minnows. Examples of predator fish 24include bass and trout. Examples of foods that are consumed by baitfishwithin the lower mesh layer 22 include plant roots, phytoplankton andother algae. The habitat provided by the lower mesh layer 22 results ina larger population of baitfish than would otherwise exist in the pond.This larger population of baitfish promotes water clarity by addingcomplexity to the food chain and utilizing nutrients for fish growththat would otherwise be used by algae.

FIG. 9 illustrates one way in which the floating island of the presentinvention can be configured to provide food and shelter for fish. Eventhe embodiments that do not include the looser mesh shown in FIG. 9 haveproven beneficial to fish populations. Specifically, it has beenobserved that fish living in ponds that contain the floating islands ofthe present invention actually grow bigger than fish that do not live insuch ponds. The reason for this phenomenon is that the floating islandsof the present invention provide food in the form of plant roots forfish to eat.

FIG. 10 is a schematic illustration of an alternative embodiment of afloating island that uses nonwoven mesh as a protective barrier forsmall fish. The island shown in FIG. 10 is comprised of a relativelytightly packed nonwoven mesh top layer 21, a relatively thin, looselypacked nonwoven mesh bottom layer 22, and buoyant spacers 25 to separatelayers 21 and 22. The packing density of the mesh in the lower layer 22is selected so as to allow small fish 23 to swim through layer 22 andinto water pockets 26 that are located between layers 21 and 22. Thewater pockets 26 provide safe resting and feeding habitats for the smallfish 23. With this embodiment, the thickness of the lower layer 22 canbe minimized because layer 22 is acting as a barrier to large predatoryfish rather than a habitat for small fish.

FIG. 11 illustrates an optional dunking feature that can be used inconnection with the nonwoven mesh embodiments of the floating islanddiscussed above. FIG. 11 is a section view of the island shown in apartially submerged or “dunked” position. The dunking feature iscomprised of a flexible line 27, a pulley 28, and an anchor block 29.The purpose of this feature is to provide water to the roots of theisland plants when these roots do not extend to the pond waterline (forexample, when the plants are immature). This feature allows a person towet the roots from shore without having to use a sprinkler. To wet theroots, the person on shore pulls on the flexible line 27, drawing itthrough the pulley 28 in the direction shown by the arrows, and causingthe island 30 to partially submerge. This action allows the water toenter the porous mesh of the island body. When the flexible line 27 isreleased, the buoyancy of the island causes it to return to its normalfloating position.

FIG. 12 is a section view of the island with optional “capillary action”features to provide water to plants that are growing above the naturalwaterline within the island. The capillary-action watering feature iscomprised of capillary tubes 31 and an absorbent top cover 32. Pondwater is drawn up through each capillary tube 31 (as shown by thedirectional arrows) and released to the absorbent top cover 32, where itis distributed to plants 33 growing above the waterline. The maximumvertical rise of water in the tubes is a function of the tube diameterand the physical properties of the water. One equation that can be usedto determine the required tube diameter for a given rise in water heightis provided in Fluid Mechanics (see reference list) as Equation 2.12:

h=(2σ cos θ/γr)

where

h=capillary rise (length)=

σ=surface tension (force per unit length)

θ=wetting angle

γ=specific weight of water

r=radius of tube

The capillary tubes 31 can be fabricated from any suitable material, forexample, flexible PVC tubing, semi-rigid polyethylene tubing, or rigidacrylic tubing.

FIG. 13 is a section view of the island with optional “wicking action”features. This embodiment is similar to the capillary-action wateringfeature of FIG. 12, except that the capillary tubes 31 are replaced bywicking units 34. The wicking units 34 are comprised of fabric orsimilar materials that have a significant wicking effect on water. Inthis embodiment, water is wicked up through the wicking units 34 andreleased to the absorbent top cover 32, where it is distributed to theplants 33.

The wicking units 34 may be preferable to capillary tubes 31 for certainapplications because they may enable a higher maximum water rise and maybe less prone to bio-fouling. One equation that can be used to determinethe theoretical maximum rise due to fabric wicking is provided in theAUTEX Research Journal (see reference list) as follows:

${H\; \max} = \frac{\begin{matrix}{{\sigma_{LG}*\cos \; \theta*2*\mu} -} \\{\left\lbrack {{2/100}*\sigma_{LG}*\left( {\mu/N} \right)^{1/2}} \right\rbrack*\left( {{Q*\left( {\cos \; \theta} \right)} + P} \right)}\end{matrix}}{R_{v}*\left( {1 - \mu} \right)*g*\rho}$

where

Hmax=equilibrium suction height

N=number of fibers in bundle

R_(V)=radius of fiber

P=% liquid from surface of bundle

Q=% non-wetted fibers from surface of bundle

-   -   μ=filling    -   ρ=density of liquid    -   σ_(LG)=interfacial tension liquid-air

θ=contact angle

For the embodiments shown in FIGS. 12 and 13, the absorbent top cover 32may be optionally planted with seeds, or coated with a mixture of seeds,adhesive, and nutrients. In either case, water will be delivered to theseeds via the capillary action shown in FIG. 12 or the wicking actionshown in FIG. 13. The mixture may be applied by any suitable means, suchas “hydroseeding,” wherein a mixture of seeds, paper mulch, and liquidadhesive is sprayed under pressure onto the surface of the island, afterwhich it dries and adheres to the fibers of the island material. In thepreferred embodiment, the capillary action of FIG. 12 and the wickingaction of FIG. 13 occurs in connection with one of the nonwoven meshembodiments of the present invention, but these innovations could beused with any floating island embodiment that includes living plants.

FIGS. 14 and 15 depict another embodiment of the present invention inwhich the floating island includes bell-shaped flotation units. FIG. 14is a first section view of the floating island 35 with optionalflotation “bells.” The bell flotation units are comprised of an aircompressor 36, tubing 37, a solenoid valve 38, a control wire 39, one ormore bells 40, and one or more internal spaces 41. The pond water level42 is also shown. In this figure, the bell flotation units are shown ina low-buoyancy position. Although the drawing depicts a system with twobells, any number may be utilized. FIG. 15 is a second section view ofthe floating island 35 with optional flotation “bells” in ahigh-buoyancy position.

Referring to FIG. 14, a signal is sent via the control wire 39, whichcauses the solenoid valve 38 to open, thereby allowing any compressedair within the internal space 41 to vent to the atmosphere. When the airpressure within the internal space 41 equalizes with atmosphericpressure, the water level within the internal space 41 will equilibratewith the pond water level 42. The arrow at the outlet of the solenoidvalve 38 represents pressurized air that is escaping from the internalspace 41 to the atmosphere. At equilibrium, the flotation bells areproviding minimum flotation to the island, and the island sinks to arelatively deep water level.

In order to raise the island to a shallower draft, a signal is sent viathe control wire 39, which causes the solenoid valve 38 to shut.Simultaneously, the compressor 36 is turned on, causing air to flowthrough the tubing 37 into the internal space 41. This air will raisethe air pressure in the internal space 41, thereby forcing a portion ofwater out of the bottom of the bell 40 (in other words, displacing thewater that is in the internal space 41). As the water within theinternal space 41 is displaced by air, the buoyancy of the bell unitincreases, thereby causing a net increase in buoyancy of the floatingisland, which causes the island 35 to rise partially out of the water.The water level can be set at any desired level between minimum andmaximum by shutting off the compressor when the desired air volume inthe internal space 41 is achieved.

The bells 40 may be fabricated from any suitable material that isimpermeable to air, strong, lightweight and durable. Suitable materialsinclude, but are not limited to, thermoplastics such as polyethylene,foamed thermoplastics such as styrene foam, and closed cell foamedmetals such as FOAMINAL, which is produced by Fraunhofer USA. Anothermaterial that shows promise for use in this application is foamedamorphous metal, which is currently being tested by LiquidMetalCorporation and other companies.

The internal space 41 may optionally be filled with highly porousmaterial that is permeable to both air and water. This highly porousmaterial may be comprised of any suitable material, including, but notlimited to, polyester mesh (such as POLY-FLO from Americo), open-cellfoamed metal (such as DUOCEL foamed aluminum from ERG Materials andAerospace), or open-cell foamed amorphous metal. One advantage offilling the internal space 41 with porous material is that it providesadditional surface area for growing beneficial microorganisms. Anotheradvantage is that it provides extra strength and rigidity to the bellunit.

The bell flotation units provide a method for adjusting the overallbuoyancy of the floating island, thereby allowing a person to manuallyadjust the draft of the island. This method can be used with anyfloating island embodiment. One advantage of this feature is that itprovides a periodic water supply to plants and seeds that are locatedabove the normal waterline, by temporarily lowering the island to anear-submerged position and then returning it to a normal position.Another advantage is that it adds buoyancy to the floating island tocompensate for the negative buoyancy created by growing plants.

FIG. 16 shows a prefabricated seeding product that provides a rapid andeasy means of seeding floating islands. The seed blanket 43 ismat-shaped, relatively thin and flexible, and may be rolled for storageand shipment. The seed blanket 43 is deployed by spreading it on top ofa floating island and fastening it in place with landscaping pins (notshown) or other suitable fasteners. The seed blanket 43 is comprised ofthree layers, including a lower seed containment layer 44, a middlecomposite seed layer 45, and an upper seed containment layer 46. Thecomposite seed layer 45 is comprised of selected aquatic plant seeds 47and optional binder 48. The binder 48 may include adhesive and/or amoisturizing agent.

The purpose of the lower containment layer 44 is to prevent the seedsfrom falling through the mesh body of the island. The lower containmentlayer 44 may be comprised of any suitable material that retains theseeds while allowing plant roots to pass through. Examples of suitablematerials for the lower containment layer include fine nonwovenpolyester mesh (such as polyester air filter material), coarse wovencloth (such as cheesecloth), and thermoplastic elastomer (“TPE”).

The purpose of the upper containment layer 46 is to prevent loss ofseeds by air or water currents prior to the time they sprout and takeroot. The thickness and density of the upper containment layer 46 mustnot be so great as to prevent the sprouted plants from penetrating theupper containment layer 46 and being exposed to sunlight. Examples ofsuitable materials for the upper containment layer 46 include finenonwoven polyester mesh (such as polyester air filter material), coarsewoven cloth (such as cheesecloth), and TPE. In some cases, it may bebeneficial to use a relatively thin, transparent material for the uppercontainment layer 46 and a thicker, denser material for the lowercontainment layer 44. In other cases, it may be preferable for both theupper and lower containment layers 44, 46 to be constructed of the sameor similar materials.

In addition to the embodiments described above, the present inventionencompasses a larger version of the floating island that is designed tosupport the weight of one or more persons. An advantage of this designis that plants growing on the floating island can be watered by walkingaround on the surface of the island, thereby temporarily causing alocalized area of the island surface to be depressed to the water level.

FIG. 17 is a section view of a first alternative embodiment of thelarger floating island. In this embodiment, the floating island iscomprised of nonwoven mesh material 4, buoyant nodules 5, supplementalflotation units 49, and stepping pads 50. The buoyant nodules 5 aredesigned to support the weight of vegetation and the above-waterlineportion of the nonwoven mesh material 4. The supplemental flotationunits 49 are each designed to support the weight of one person, and theymay be comprised of any material that is suitably buoyant and durable.Examples of suitable materials for the flotation units includepolyurethane foam sealant and closed cell polymer foam. The steppingpads 50 provide a non-slippery walking surface and indicate theallowable areas for walking, and they may be comprised of any materialthat is suitably durable and slip resistant. Examples of suitablematerials for the stepping pads include outdoor carpeting and syntheticstones made of molded fiberglass. The buoyant nodules may or may not benecessary depending on the degree of buoyancy provided by thesupplemental flotation units.

FIG. 18 is a section view of a second alternative embodiment of thelarger floating island. The design of the island shown in FIG. 18includes the features of the island shown in FIG. 17, plus additionalload distribution members 51. When a person steps upon a particularstepping pad 50, the load distribution members 51 distribute theperson's weight to several of the supplemental flotation units 49,thereby reducing the distance by which the stepping pad would otherwisemove downward. This reduction of downward displacement provides a morestable walking surface than the design shown in FIG. 17. The loaddistribution members can be made of any suitably durable, lightweightand rigid material. Examples of suitable materials for the loaddistribution members include PVC pipe and aluminum channels. Twoadditional materials that may be particularly well suited for thisapplication are metal foam and amorphous metal foam (currently in thedevelopment phase). Compared to thermoplastics, these two materialsexhibit extremely high strength-to-weight ratios and long-termdurability.

In order to provide the required load distribution (and thereby preventlocal sagging) of the island surface due to point loads (such aspersons) supported by the island, the load distribution members musthave sufficient stiffness. The stiffness of a pipe is a function of thepipe diameter, the pipe wall thickness, and the bending modulus of thepipe material. Depending on the size of the island and the design loads,useful pipe diameters may range from about one inch to about 18 inches;useful wall thickness may range from about 1/16 inch to about one inch;and useful bending modulus may range from about 5,000 pounds per squareinch (psi) to 500,000 psi, as measured by ASTM Standard D747-02. Thesesame principles would apply to hose or any other material from which theload distribution members are constructed.

The islands shown in FIGS. 17 and 18 may be assembled on-site near thewater edge. When this on-site method of assembly is employed, theislands may be deployed by pushing or pulling the islands into the waterwith a truck or other mechanized equipment. In order to prevent damageto the structure of the island during installation, the edge of theisland coming into contact with the truck or other mechanized equipmentmay be reinforced with a load-bearing and/or load-distributingprotective cover (not shown). This cover may be comprised of semi-rigidthermoplastic, such as polypropylene or PVC sheeting.

FIG. 19 shows top views of an artificial stepping stone 52 andartificial tree limb 53. These items may be manufactured form anybuoyant, rigid and durable material, such as CAST ALL, which is atwo-part expandable polymer foam available from Westco Supply in RanchCordova, Calif.

FIG. 20 shows three alternative methods for using the artificialstepping stone 52 and artificial tree limb 53 that are shown in FIG. 19.In the left example, the stepping stone flotation assembly 54 iscomprised of a lower stepping stone 55, an upper stepping stone 56, anda connecting cable unit 57, which firmly attaches the stepping stones55, 56 to the island body 58. The island body 58 may be comprised of anyof the types of islands that have been previously described. Theconnecting cable unit 57 may be comprised of plastic rope or rustproofmetal cable. When the island body 58 is floating normally, the lowerstepping stone 55 is submerged and, therefore, provides buoyancy to theisland structure. When the island structure is abnormally submerged(e.g., when a person steps upon the island), the upper stepping stone 56also becomes partially or fully submerged and thus provides additionalbuoyancy to the structure.

In the middle example, the stepping stone/vertical buoyant memberflotation assembly 59 is comprised of an artificial stepping stone 52and a vertically installed buoyant member 60. The buoyant member 60 maybe comprised of air-filled or closed cell foam-filled plastic pipe orother similar material. The buoyant member 60 may be attached to theisland body 58 by adhesive (not shown), cable ties (not shown) or otherconventional means.

In the right example, the floating tree limb assembly 61 is comprised ofa lower artificial tree limb 62, an upper artificial tree limb 63, and aconnecting cable assembly 57. The lower tree limb 62 is normallysubmerged, thus providing buoyancy to the island structure. Additionalbuoyancy is provided to the structure when the upper tree limb 63 isalso partially or fully submerged. It should be noted that the buoyantcomponents (the stepping stones 52, 55, 56 and the tree limb 53, 62, 63)may be replaced with conventional buoyant building materials such asclosed cell foam blocks or cylinders (not shown). The natural shapes ofthe stepping stones 52, 55, 56 and tree limbs 53, 62, 63, however,provide aesthetic appeal to the structure.

FIG. 21 is a perspective view of a framework that could be used inconjunction with any floating island structure to provide adjustablebuoyancy. In the preferred embodiment, it is used in connection with thenonwoven mesh island. FIG. 21 shows the horizontal and verticalcomponents of a variable buoyancy, rigid framework 64. The horizontalmembers 65 are comprised of hollow plastic pipe or other similarmaterial. These horizontal members 65 may be installed either below orwithin the mesh matrix body of the island (not shown). The overallbuoyancy of the structure is designed so that the horizontal members areset below the waterline. Optionally, the buoyancy of the horizontalmembers 65 can be adjusted by filling the interior space of the memberswith water, air, or a combination of both. In one embodiment, waterenters the horizontal members 65 via a water tube 66 when the aircontrol valve 67 is open to the atmosphere. Water can be displaced fromthe horizontal members 65 by blowing compressed air into the air tube68, thereby forcing water out through the water tube 66. After the wateris displaced, the air control valve 67 is closed, which prevents waterfrom reentering the structure. Alternatively, the horizontal members canbe filled with foam to increase buoyancy. The buoyancy of the island canalso be increased by adding additional horizontal members.

In an alternative embodiment, shown in FIG. 22, the horizontal membersare comprised of a perforated pipe section 69 and an inner, inflatablebag 70. In this figure, the central portion of the pipe section 69 hasbeen removed to show the inflatable bag 70. The inflatable bag 70 isshown in a deflated state, which allows water to enter the perforatepipe through holes 71. When the inflatable bag 70 is deflated, thehorizontal members are in a low-buoyancy condition. In order to increasethe buoyancy of the horizontal members, an air control valve 67 isopened, and compressed air is forced through an air tube 68 into theinflatable bag 70. As the inflatable bag 70 expands, water is forced outof the pipe through the holes 71, thereby causing an increase inbuoyancy. After the inflatable bag 70 is filled with sufficient air toprovide the desired degree of buoyancy, the air control valve 67 can beclosed. This embodiment may provide a more reliable method of varyingthe buoyancy of the horizontal members than simply filling the pipeswith air because the inflatable bag 70 will maintain buoyancy even ifthe pipes sustain cracks or leaks over time. The pipes 69 serve as aprotective cover for the inflatable bag 70 against puncture and abrasiondamage from floating debris and animals.

Referring again to FIG. 21, additional adjustable buoyancy is providedto the rigid framework 64 via the lower vertical member 72 and the uppervertical member 73, which are comprised of hollow plastic pipe orsimilar material. In a preferred embodiment, the vertical members 72, 73are joined with threads or another appropriate non-permanent connection.Alternatively, the vertical members can be joined permanently. Theinterior of the vertical members 72, 73 may be left open or optionallyfilled with buoyant material such as expandable foam sealant (e.g., DowChemical's FROTH-PAC). The lower end of the lower vertical member 72 issealed with a watertight end cap 74. The buoyancy of the framework 64 isadjusted by sliding the vertical members 72, 73 upward or downwardwithin the collar 75, as shown by the arrows. If a relatively smallamount of buoyancy is desired, the lower vertical member can be raisedto the maximum height and locked into position with a locking pin 76,which is placed through the locking pin holes 77. If desired, the uppervertical member 73 may be detached from the lower vertical member 72.

To increase the buoyancy of the structure, the locking pin 76 is removedand the vertical members 72, 73 are pushed downward, deeper into thewater. The vertical members are then locked into the new position viathe locking pin 76. If required, an additional vertical member (notshown) may be connected to the top of the upper vertical member 73, andthe vertical members may be positioned even deeper into the water.Locking straps 78 are used to keep the framework 64 attached to the meshmatrix body of the island (not shown).

In addition to providing buoyancy to the floating island, the framework64 provides a rigid, load-distributing understructure, which can help tosupport the weight of persons walking on the island. The design of theframework 64 allows the buoyancy to be evenly distributed across thesurface of the island, thereby eliminating “high spots” and “low spots”that would otherwise be produced by unconnected buoyant nodules locatedwithin the island body. Launching the floating island structure fromshore into the water after construction may be facilitated by addingoptional wheels 79 and/or skids 80 to the horizontal members 65 of theframework. The wheels and/or skids are preferably buoyant. If thehorizontal members are sufficiently rigid, they can serve as skids, thusfacilitating the launch of the island into the water without damagingthe matrix and eliminating the need to add separate skids.

FIG. 23 shows yet another embodiment of an adjustably buoyant frameworkfor a floating island. In this embodiment, the framework is comprised ofprefabricated flotation tubes 81 and prefabricated cross members 82.Each flotation tube 81 is comprised of protective pipe 83, an inflatabletube 70, an air tube 68, and an air control valve 67. Each prefabricatedcross member 82 is comprised of a strap 84, a plurality of pipepositioning devices 85, and a plurality of island body attachment posts86. The purpose of the flotation tubes 81 is to provide buoyancy to theisland structure and rigidity to the island surface. The purpose of thecross members 82 is to maintain the flotation tubes at the properspacing, to provide additional rigidity to the island surface, and toprovide a means for attaching the framework to the body of the island.The purpose of the protective pipe 83 is to prevent damage to theinflatable tube 70. The purpose of the inflatable tubes 70, air tube 67,and air control valves 68 is to provide a means for independentlyvarying the buoyancy of each flotation tube 81, thereby providing anadjustable buoyancy across the surface of the island that can be used tocompensate for varying and non-uniform loads that are placed (or growupon) the island. The buoyancy in each flotation tube 81 is increased byincreasing the degree of inflation in the inflatable tube 70, whichdisplaces water from the inside of flotation tube 81. The buoyancy isdecreased by reducing the degree of inflation in inflatable tube 70,thereby allowing water to enter flotation tube 81.

In a preferred embodiment, the cross members 82 are manufactured inseveral standard lengths, such as five feet, ten feet and fifteen feet.The straps 84 may be comprised of any relatively stiff andcorrosion-resistant material, such as galvanized steel channels,aluminum tubing or rigid plastic tubing. The pipe positioning devices 85are attached in pairs to the straps 84 by conventional means, with apositioning device 85 on each side of a pipe 83. The island bodyattachment posts protrude through holes cut into the island body (notshown). Nuts and washers (not shown) are used to secure the island bodyto the attachment posts 86. The flotation tubes 81 can be manufacturedin several standard lengths, such as five feet, ten feet and fifteenfeet. They are comprised of materials as previously described inconnection with FIG. 22.

The framework depicted in FIG. 23 can be quickly assembled to fit anyfreeform island shape by using an appropriate assortment ofprefabricated flotation tubes 81 and cross members 82. The cross members82 can alternatively be positioned above the flotation tubes 81. Thisconfiguration provides a flat base for the island body. Although thepipe positioning devices 85 are shown in this figure to be comprised ofbracket-types fixtures, any conventional positioning fixture could beused. Although the cross members are shown to be rectangular in crosssection, other cross section shapes, such as angles, channels or tubingcould be used.

FIGS. 24 and 25 illustrate two different methods for adding buoyancy toan island whose overall buoyancy has decreased over time due to plantgrowth or other conditions. If desired, these methods may be employedwithout removing the island from the water.

FIG. 24 shows a section view of an island with single attachment pointflotation units 87. The left and center flotation units 87 utilizebarbed spikes 88 for attachment. The barbed attachment spikes 88 may bemade from corrosion-resistant metal, such as aluminum, or rigid plastic,such as PVC. The floats 89 may be commercially available fish net floatsor similar objects made form any suitably buoyant and durable material.The spikes 88 are positioned within a hole inside the floats 89. Theleft flotation unit 87 in the figure is shown prior to attachment to theisland body 58. The arrow shows the direction of movement required topush the flotation unit 87 into the bottom of the island body 58. Thebarb on the head of the spike 88 allows the flotation unit 87 to bepushed into the mesh material of the island body 58, thereby preventingthe flotation unit 87 from slipping out. The center flotation unit 87 isshown in the attached position after the barb has been inserted into theisland body 58. The right flotation unit 87 is shown attached to anartificial rock or other buoyant feature 90 by means of a retaining pin91.

In FIG. 25, a dual-ring buoy 92 is attached to landscaping pins 12 bymeans of conventional snap-on connectors 93. The landscaping pins 12 maybe installed into the island body 58 during original construction, orthey may be installed subsequent to construction of the island.

FIG. 26 illustrates the use of receivers for mounting equipment oraccessories on the floating island of the present invention. In FIG. 26,a fully penetrating receiver unit 94 is shown installed into the leftportion of an island body 58. The fully penetrating receiver unit 94 iscomprised of a length of pipe 95, a lower flange 96, and an upper flange97. The pipe 95 may be joined to flanges 97, 98 via threaded endconnectors or glue joints. The pipe 95 is installed through a hole (notshown) that is cut, drilled or otherwise fabricated in the island body58. A partially penetrating receiver unit 98 is shown on the right sideof the island body 58 and is comprised of an upper flange 97 and alength of pipe 95 that does not penetrate the lower edge of the islandbody 58. The main purpose of the receiver units 94, 98 is to provide amounting location for equipment or accessories such as solar panels,wind generators, or decorative items (not shown) that may be desirablefor a particular island configuration. A plurality of receiver units 94,98 may be installed on an island. A secondary purpose of the receiverunits 94, 98 is to provide a means for locking together multiple layersof material within the island body.

FIG. 27 illustrates a method of using the floating island of the presentinvention to bolster a shoreline. In this figure, the protectivefloating structure 99 is comprised of nonwoven mesh matrix 4, buoyantnodules 5, and optional plants 33. A conventional anchor or tether (notshown) may be used to maintain the position of the structure 99 relativeto the shoreline 100. The structure 99 can be used to prevent erosion tothe shoreline 100 by serving as an energy-absorbing damper to waves 101.The structure 99 can also serve as a protective barrier to preventfloating objects (such as boats or logs, not shown) from striking theshoreline 100. The depth of the floating island can be adjusted toaccommodate whatever level of shore or bank erosion protection isdesired.

With respect to any of the above embodiments, additional thin andlightweight island modules may be attached around the perimeter of themain central floating island in order to provide additional shade andplant growth area, thereby increasing the water quality benefits of theisland. These additional island modules can be made of a single layer ofnonwoven mesh material or similar suitable material, impregnated withbuoyant material. While the central floating island could support largerplants, these “satellite” module islands could support short plants suchas grasses and sedges. In addition, any of the embodiments of thepresent invention could be combined with artificial vegetation, ifdesired, for additional cosmetic effect.

FIG. 28 shows a group of identical, mass-produced floating islands (madeof nonwoven mesh material) that are connected to form a single largeisland. FIG. 28 is a top view of four identical, mass-produced islands102 that are joined with four connectors 103 to form a modular islandstructure 104. The connectors 103 are comprised of nonwoven matrixmaterial. The connectors 103 may optionally be treated with bondedgrowth medium (described below) or other materials to promote plantgrowth. The plant-sustaining ability of the connectors 103 contributesto the visual appeal and biological diversity of the structure, whilethe mass-produced islands 102 provide a cost-effective manufacturingtechnique.

In yet another embodiment of the present invention, concentric multiplecutouts provide numerous islands with reduced constructions costs. FIG.29 shows a first island 105 from which the central portion has beenremoved, creating a second island 106 and a central opening 107 withinthe first island 105. The central portion of the second island 106 hassimilarly been removed, creating a third island 108 and a centralopening 109 within the second island 106.

The multiple concentric cutout design shown in FIG. 29 provides asignificant reduction in materials required for construction of islands,thereby providing a significant cost saving for manufacture. AlthoughFIG. 29 shows a total of three islands, this number will vary dependingon the size of the first island 105 and the desired size of the lastisland.

FIG. 30 shows a perspective view of a skeleton frame island 110 createdby using the multiple concentric cutout method. The skeleton frameisland 110 is comprised of a skeleton frame 111, a floor 112, one ormore optional dividers 113, and buoyant intrusions 114. The skeletonframe, floor and dividers are all preferably comprised of nonwoven meshmaterial.

FIG. 31 shows a section view of skeleton frame island 110 taken at lineB-B of FIG. 30. As shown in FIG. 31, the skeleton frame island 110 iscomprised of skeleton frame 111, floor 112, divider 113, buoyantintrusions 114, soil growth medium 115, soil-based plants 116, andmatrix-based plants 117. Matrix-based plants are plants that are grownon portions of the island that are comprised of the nonwoven meshmaterial. The matrix-based plants may be started from either seeds orrooted plants that are installed into the matrix. Seeds may be sprinkledonto the top of the matrix and may optionally be bonded to the matrixfibers with any suitable adhesive. Rooted plants are installed intoprecut holes within the matrix.

The soil growth medium 115 is comprised of natural organic material 118,such as peat, and of synthetic organic material 119, such as pieces ofnonwoven polyester scrap material. Bonded growth medium (not shown,described more fully below) may be infused into the skeleton frame 111,floor 112, and/or divider 113. The bonded growth medium provides adurable environment for seed germination and plant growth.

The relative growth rates of soil-based plants 116 and matrix-basedplants 117 may be controlled by adjusting the nutrient concentrationsand interstitial spacings of the soil growth medium 115 and skeletonframe 111. For example, by setting the nutrient level in the soil growthmedium 115 higher than the nutrient level in the skeleton frame 111, theroots of the matrix-based plants 117 will grow faster, while the tops ofthe soil-based plants will grow faster. Similarly, plant growth ratesmay be manipulated by adjusting the percentage of interstitial space inthe soil growth medium 115 and skeleton frame 111. For example, addingmore synthetic organic material 119 to the natural organic material 118will increase the volume of interstitial spaces within soil growthmedium 115, thereby increasing the growth rate of microbes andmacrophytes within the soil growth medium 115.

With the skeleton-frame embodiment described above, the growth rates ofplant roots on different zones of the island can be manipulated toimprove the value of the island for fish and wildlife habitat. In apreferred embodiment, the nutrient levels in the perimeter zone (theskeleton frame) are set at a relatively low level by using bondingagents without added nutrients around the perimeter, while the nutrientlevels in the center soil growth medium area are set at a relativelyhigh level by placing nutrient additives into the soil growth mediummixture. In this embodiment, the roots of plants in the perimeter zonewill grow rapidly through the matrix into the pond water in search ofnutrients, thereby forming an underwater perimeter “curtain” of roots.Conversely, the roots of plants in the central nutrient-rich soil growthmedium zone will be able to obtain sufficient nutrients from arelatively small root mass; therefore, these roots will be slow topenetrate through the matrix into the water below. By this means, anunderwater root zone will be formed under the island that has arelatively long, dense outer ring and a relatively short, slender-rootcenter area. This embodiment will be attractive to small fish that seekrefuge and food within the inner area because larger predator fish willbe excluded by the outer ring.

The skeleton-frame island embodiment of the present invention is capableof supporting plant growth over its entire surface area, whileconventional “floating planters” have a non-permeable flotation ringaround their perimeter that is not capable of supporting plant growth.The ability of the skeleton frame island embodiment of the presentinvention to support plant growth over the entire surface offerssignificant advantages for water-quality applications, as well asproviding a more natural, visually appealing appearance thanconventional floating planters.

Nonwoven mesh scrap material from the cutting and shaping of theskeleton frame 111 and floor 112 may provide a low-cost source ofsynthetic organic material 119. Adding synthetic organic material 119will also reduce the saturated weight of the soil growth medium 115,thereby reducing the volume of buoyant intrusions 114 required to floatthe skeleton frame island 110.

FIG. 32 shows two alternative embodiments for installing plants and soilgrowth medium into a skeleton frame island. FIG. 32 is a side sectionview of a skeleton frame island 110 with two growth compartments 120 and121 separated by a divider 113, and a prefabricated planter unit 122shown prior to installation. The first growth compartment 120 is filledby placing soil growth medium 115, plants 116 and seeds (not shown) intothe growth compartment 120 by hand. The second growth compartment 121 isfilled by placing a prefabricated planter unit 122 into the compartmentas shown by the arrow. The prefabricated planter unit 122 may be grownand shipped separately from the skeleton frame island and installed atthe deployment site. The prefabricated planter unit 122 may have certainadvantages, including the ability to culture plants professionally priorto installation, easy installation and replacement, and cost savings.

The prefabricated planter unit 122 is comprised of a shell 123, soilgrowth medium 115, optional plants 116 and optional seeds (not shown).The shell 123 is comprised of a material such as coir or nonwovenpolyester matrix that is permeable to water and penetrable by plantroots.

The soil growth medium 115 may include pH buffers and modifiers tooptimize plant growth for specific conditions. For example, when anisland is deployed in acidic pond water with plants that prefer neutralor alkaline pH water, the soil growth medium can comprise calciumcarbonate or other similar substance that increases the pH of the watersurrounding the plant roots, thereby giving these roots an optimizedgrowth environment during their early growth stage. Similarly,substances that reduce the pH of water can be added to the soil growthmedium 115 when an island is deployed in alkaline waters with plantsthat prefer neutral or acidic pH. Peat is an example of a material thatcan provide an acidic pH environment.

The present invention also encompasses a bonded growth medium that isoptimized for germinating and nurturing plants in an aquatic setting.The bonded growth medium of the present invention is designedspecifically to be used as a component of a floating island, although itmay be used in other applications as well. As described more fullybelow, the bonded growth medium encompasses a number of optionalfeatures to optimize it for various conditions and for use with avariety of plant species. The bonded growth medium is described below asused with islands comprising a continuous matrix top surface, but can beequally well employed with the skeleton frame island embodiment.

FIG. 33 is a top view of a floating island 124 with bonded growthmedium, shown prior to plant growth. FIG. 34 is a section view of thefirst embodiment of the bonded growth medium taken at section C-C ofFIG. 33, in which the bonded growth medium 125 is attached to the outersurface of the floating island 124. The island 124 shown in FIG. 34 iscomprised of bonded growth medium 125, porous matrix 126, buoyantinclusions 127, and optional capillary channels 128. Porous matrix 126may be comprised of any lightweight, porous material penetrable by plantroots. An example of a suitable material is POLY-FLO filter mesh,manufactured by Americo. Buoyant inclusions 127 may be comprised of anynontoxic buoyant material, such as closed cell foam or polyurethanespray foam. Capillary channels 128 are vertical holes cut into thematrix 126 and filled with any suitable wicking material. The purpose ofthe capillary channels 128 is to transport water through the islandmatrix 126 and supply it to the bonded growth medium 125 on the top andedges of the island. In a first embodiment, the wicking material in thecapillary channels 128 is comprised of peat, polyester felt, or othersuitable natural or synthetic material. In a second embodiment, thecapillary channels 128 are filled with bonded growth medium.

As shown schematically in FIG. 35, the bonded growth medium 125 iscomprised of peat fibers (or similar material) 129, binder 130, optionalembedded seeds 131, optional topcoat seeds 132, optional nutrientparticles 133 and optional buoyant pellets 134. Other optional materials(not shown) include shredded paper, shredded wood, and lightweightsynthetic materials. Beneficial microbes (not shown), which includefungi and bacteria, may also be optionally included in the bonded growthmedium. By varying the components of the bonded growth medium, the waterretention, buoyancy, nutrient level, pH, porosity, interstitial spacevolume, and other parameters can be modified to optimize for a specifictype of plant (e.g., aquatic versus flowering terrestrial), a particularwater body (e.g., alkaline or acidic), a particular island shape (e.g.,low-floating versus high-floating), or even to create an optimalenvironment for the growth of beneficial microbes.

The first purpose of the peat fibers 129 is to retain water and absorbradiant sunlight energy, thus providing optimal conditions for plantgermination and growth. The second purpose of the peat fibers 129 is toprovide a natural, visually appealing surface. A third purpose of thepeat fibers is to prevent sunlight from contacting the fibers within thematrix, thereby preventing the growth of algae within the matrix. Afourth purpose of the peat fibers is to reduce the pH of water adjacentto plant roots. The purpose of the binder 130 is to attach the peatfibers 129 and seeds 132, 133 to the matrix 126, and to prevent themfrom being lost due to wind or wave action. Nutrient particles 133 maybe comprised of commercial slow-release plant fertilizer or similarmaterial. Buoyant pellets 134 may be comprised of perlite, polystyrene,or other lightweight closed cell materials. The buoyant pellets provideadditional buoyancy to the structure if required for a particularapplication.

The first purpose of the bonded growth medium 125 is to provide anoptimal growth environment for seeds and plants. A second optionalpurpose of the bonded growth medium 125 is to provide a low-permeabilitygas barrier around the outer surface of the island, thereby trappingwithin the body of the island water vapor and gases produced bymicrobes. The water vapor minimizes “air pruning” of plant roots, andthe other gasses provide additional buoyancy to the island structure.The bonded growth medium 125 also serves as a protective agent toprevent deterioration of the matrix 126 and buoyant inclusions 127 byambient ultraviolet (“UV”) sunlight. The UV protection may be providedby the natural light-absorbing qualities of the peat fibers or similarmaterial 129, or the UV protection of the bonded growth medium 125 canbe boosted by adding a UV-blocking agent to the uncured bonded growthmedium mix prior to application. One example of a suitable commonUV-blocking agent is carbon black.

In one embodiment, the binder 130 is comprised of a porous and permeablematerial, such as open cell polyurethane foam or cellulose (similar tokitchen sponges). In this embodiment, the binder transports water to theseeds 131, 132 and plants (not shown) from the capillary channels 128,or from the water body (not shown) in which the island is floating. Inanother embodiment, the binder 130 is comprised of nonporousthermoplastic such as TPE or other nonporous, non-permeable bindermaterial. In this embodiment, the ratio of peat fibers 129 and binder130 is designed so that the proportion of peat fibers 129 is sufficientto serve as the water transport medium through the bonded growth medium125.

The bonded growth medium 125 is preferably manufactured as a viscousliquid in the uncured state, which changes to a flexible solid aftercuring. The uncured bonded growth medium 125 is poured or sprayed overthe top of the matrix and binds to the matrix 126 during the curingprocess. An infiltration zone 135 occurs where bonded growth medium 125infiltrates into the matrix 126 prior to curing. In the case where thetemperature of the uncured bonded growth medium 125 is low enough forseeds to survive, the embedded seeds 131 may be added to the mixtureduring manufacture, and the topcoat seeds 132 may be sprinkled onto theuncured bonded growth medium 125 after it has been applied to the matrix126. In the case where the temperature of the uncured bonded growthmedium 125 is excessive for seed survival, embedded seeds 131 may beinstalled via holes punched into the partially or fully cured bondedgrowth medium 125 after it has cooled sufficiently, and topcoat seeds132 may be attached by a conventional nontoxic adhesive.

FIG. 36 shows an island 124 comprised of individual layers of nonwovenmesh material 4 that have been stacked and bonded together. Also shownare buoyant inclusions 127 and capillary channels 128, which areidentical to those items previously described for FIG. 34. In thisembodiment, the components of the bonded growth medium are embeddedwithin the matrix layers 4 rather than being applied to the top of thematrix 126, as shown in FIGS. 34 and 35.

FIG. 37 is a magnified view of a portion of FIG. 36, showing thecomponents of the embedded bonded growth medium. Peat fibers (or similarmaterial) 129, binder 130, optional embedded seeds 131, optionalnutrient particles 133 and optional buoyant pellets 134 are all similarto the materials described in connection with FIG. 34.

The embedded bonded growth medium shown in FIGS. 36 and 37 can bemanufactured in at least three different ways. A first method involvesincorporating the components of the bonded growth medium into the matrixlayers 4 during the manufacturing process of the matrix. For example,when the matrix layer 4 is comprised of nonwoven polyester mesh (e.g.,Americo's POLY-FLO), then the peat fibers 129, nutrient particles 133and buoyant pellets 134 may be added into the mixing hopper along withthe raw polyester fibers. All of the materials are then bonded togetherwhen latex binder is added to the matrix.

A second method of manufacturing the embedded bonded growth mediuminvolves injecting the uncured bonded growth medium into each sheet ofmatrix prior to stacking. This method can be used in connection withnonwoven mesh materials such as Americo's POLY-FLO, which is typicallysupplied in two-inch thick sheets. Multiple layers of matrix sheets arestacked and bonded to make a floating island, as shown in FIG. 36. Theuncured bonded growth medium may be injected into the matrix by pressurespray with optional vacuum assist applied to the back side of thematrix, by point injection via a tube inserted into the matrix, or bygravity infiltration of a low-viscosity blend of uncured bonded growthmedium into the matrix.

A third method of manufacturing the embedded bonded growth mediuminvolves stacking the matrix layers prior to injecting the bonded growthmedium. Injection is accomplished as described above. In thisembodiment, the bonded growth medium may act as an adhesive to bond thelayers of matrix.

As alluded to above in connection with the discussion of FIGS. 1-5, acommon feature of all of the nonwoven mesh material floating islandembodiments of the present invention is that they can serve as abiofilter in at least two respects. First, the island exposes phosphorusand other nutrients found in pond water to the microorganisms (which canbe anaerobic or aerobic) present on the island's polymer matrix and/orin the bedding matrix, growth medium, or plant roots. These nutrientshelp sustain the microorganisms, which contribute to pond and planthealth. Second, the island can also act as a means of dispersing certainbeneficial microorganisms, including, but not limited to, fungi,throughout a pond or other water body. This dispersal of microorganismsis accomplished as the water that is filtered through the island carriesoff a fraction of the island's population of microorganisms. Thesebeneficial microorganisms can be naturally occurring, or they can beintroduced onto or into the floating island by artificial means.

Further contributing to the filter effect, the plants that are grown onthe island can be selected on the basis of their ability to contributeto the removal of phosphorus and other nutrients from the water body.Specifically, the wetland plants that utilize phosphorus in largequantities include: Scirpus validus (Bulrush), Phragmites communis(common reed), and Typa latifola (cattail). Plant uptake of phosphorusduring the algae growing season will reduce the amount of phosphorusavailable for algae production and thereby impact the eutrophicationprocess. It is expected that the types of plants listed above, if grownon the floating island of the present invention, could reduce theoverall phosphorus concentration in the water passing through thefloating island by 40 to 70%. The amount of nutrients removed by thisprocess will be proportional to the hydraulic loading rate for theisland (i.e., the rate at which water passes through the island).Various mechanisms, such as a water pump, could be used to increase thehydraulic loading rate and, therefore, the amount of nutrient removed.In addition, the structure of the island could be adjusted to takemaximum advantage of its filtering capacity. For example, the profile ofthe island above the water surface could be increased to a higher levelin order to provide a greater unsaturated volume of media through whichwater could be filtered.

To enhance the filter effect of the present invention, a waterdistribution system may be used to pump water from beneath the islandand spread it across the surface of the island, allowing the water topercolate through the fibers of the island matrix (or the nonwoven meshmaterial) for biological treatment. FIG. 38 is a schematic depiction ofa first embodiment of a floating island 136 with a pumped waterdistribution system 137. The path of water flowing through the system isshown by arrows. The island 136 is comprised of nonwoven mesh 4 plusother materials (not shown). The water distribution system 137 iscomprised of a water pump 138 and distribution pipes 139. FIG. 39 is atop view of the water distribution system that shows schematically thedistribution pipes 139. This particular water distribution system isdesigned to distribute water over the surface of the island while notrestricting upward plant growth. The purpose of the water distributionsystem 136 is to pump untreated pond water from beneath the island andspread it across the surface of the island, whereby it can percolatethrough the fibers of the nonwoven mesh 4 for biological treatment. Formaximum treatment efficiency, it is important to distribute the waterthroughout the entire volume of the nonwoven mesh 4.

FIG. 40 is a section view of a second embodiment of a floating islandwith a pumped water distribution system. The system is comprised of awater pump 138, nonwoven mesh island body 140, nutrient-uptake aquaticplants 141, and water-impermeable enclosure tray 142. For purposes ofthis description, the term “nutrient-uptake aquatic plants” refers toaquatic plants that absorb and incorporate nutrients found in the water.One example of a highly effective nutrient-uptake aquatic plant is thecattail (genus Typha).

The system shown in FIG. 40 works by pumping nutrient-rich pond waterfrom beneath the island and circulating it radially outward through theisland body 140. The path of the circulated water is indicated by thearrows in the figure. Optional air bubbles 143 may be provided from anexternal air source (not shown). In this figure, the water pump 138 isshown as extending vertically through the center of the island, but thewater pump 138 could be positioned in any manner that allows it to pumpwater through the island. In the illustrated example, the water flowsthrough the island body 140 from the center toward the edges and exitsthe island body 140 through perforations 144 in the perimeter of thetray 142. The purpose of the tray 142 is to ensure that the flowingwater does not escape through the bottom of the island, therebymaximizing its exposure time for uptake by the plants 141 and fortreatment by microorganisms (not shown) that are attached to the fibersof the island body 140 and the roots of plants 141.

In a preferred embodiment, the tray 142 is constructed of lightweightplastic, such as polyethylene, that is impermeable to both water andplant roots. In an alternative embodiment, the tray 142 is constructedof a material such as TPE that is impermeable to water but that iscapable of being penetrated by growing plant roots. The islandessentially sits in the tray, and the tray is attached to the floatingisland by any conventional fastening method.

The purpose of the optional air bubbles 143 is to increase the rate ofaerobic conversion of nutrients by microbes. The energy source for thecompressed air (not shown) that produces these bubbles may be utilityelectricity, solar-electric, wind-mechanical, wind-electric, or othersuitable means.

In addition to the beneficial effects discussed above, the floatingislands of the present invention can also facilitate the process ofcarbon sequestration, which has become the subject of relatively newinternational environmental policies that provide financial incentivesfor growing plants that sequester carbon. Carbon sequestering isaccomplished by growing plants that uptake carbon dioxide from theatmosphere and convert it via photosynthesis to organic carbon withinthe plant. This process reduces the greenhouse effect of atmosphericcarbon dioxide by reducing the concentration of carbon dioxide in theatmosphere. In floating islands, carbon dioxide is reduced by directremoval from the atmosphere by the plants, and it is also reduced bymicrobial processes occurring below the waterline within the rootcommunity and matrix of the islands. When dissolved carbon dioxide isremoved from water, it causes a corresponding reduction in atmosphericcarbon dioxide because carbon dioxide will migrate from the air to thewater in order to reestablish equilibrium between atmospheric anddissolved gas phases after the dissolved gas concentration in the wateris reduced by the islands. Floating islands offer a novel and uniquemeans for sequestering carbon because they can be installed at locationswhere typical carbon-sequestering plants (e.g., pine trees) cannotthrive.

The floating islands of the present invention can be positioned overnutrient-rich, oxygen-depleted marine zones, such as the “dead zone” inthe Gulf of Mexico. The term “dead zone” generally refers to thesituation in which nutrient-rich water flows into an ocean from a river,algae in the ocean water near the surface consume those nutrients andproduce oxygen in the process, the algae cells eventually die and sinktoward the bottom of the ocean, where the algae cells consume oxygen asthey decay. Due to the large number of algae cells falling to the bottomof the ocean, all of the oxygen near the bottom is consumed, and thereis no oxygen left in the water for fish, lobsters, or other animals,thus creating a “dead zone” near the ocean bottom. Within the dead zone,the water is nutrient-rich but oxygen-poor. Above the dead zone, nearthe ocean's surface, the water is both nutrient- and oxygen-rich.

In this situation, water from the dead zone can be pumped over theisland (e.g., by windmills on the island), where it will providenutrients to plants growing on the island. The plants on the island usesunlight energy to combine carbon dioxide from the air with nutrients inthe water to make plant mass. This process removes carbon dioxide fromthe air (reducing the greenhouse effect) and sequesters the carbon inplant biomass. Additionally, when the “dead zone” water is pumped to thesurface, new water circulates into the dead zone to replace the waterthat has been pumped out. This process accomplishes two beneficialeffects: reduction of the dead zone and carbon sequestration.

In order to maximize the cost effectiveness of marine-based,carbon-sequestering islands, the islands can be designed so that theyare “self-growing” by selecting plants that will provide lateralexpansion of the surface of the island during their normal growth anddeath cycle. Examples of marine plants that could create their ownsubstrate and expand laterally include seaweeds of the genera Eucheumaand Kappaphycus. Examples of plants that may tolerate a salineenvironment include Sea Rush (Juncus maritimus), Sea Lavender (Limoniumlatifolia) and similar species. By fostering the growth of plants thattolerate saline environments and provide lateral expansion, theoriginally installed islands act as “island seeds” that grow larger overtime.

Another method that could be used to expand the surface area of thefloating islands of the present invention involves a biological adhesiveand bonding process, such as that described for the marine musselMytilus edulus in the book Biomimicry (Janine Benus, HarperCollins,1997). The mussel produces cross-linked strands of protein with veryhigh cohesive and adhesive properties, and the mussel-produced adhesivecan be applied underwater. This adhesive material would be useful forbonding matrix fibers in the floating islands, for “growing” islandsafter deployment, and for trapping sediment particles from the water,thereby improving water clarity. “Growing the islands” could beaccomplished by periodically dosing the edges of an island withbiological adhesive. Because the adhesive remains sticky when wet, itwould tend to catch debris such as grass, leaves and twigs floating inthe water. This debris would adhere to the edges of the island andprovide a substrate for plant growth, thereby causing the island toexpand laterally. The adhesive would also trap fine waterborne andwindblown sediment particles that contact the island. The biologicaladhesive could be manufactured by mussels or reproduced synthetically ina laboratory.

FIG. 41 illustrates a floating island that can also serve as a boatdock. This feature would be useful for docking at the islands forreplanting, maintenance, hunting, fishing or photography. FIG. 41 showsa top view of a floating island 145 constructed in a shape that isdesigned to provide a boat docking location 146. The boat dockinglocation 146 is shaped so that the docked boat is mostly surrounded byisland material. Low abrasion padding 147 (such as closed cellpolyethylene foam or fine nonwoven polyester mesh) may optionally beplaced around the inner perimeter of the docking area to provide extraprotection for the boat hull.

The integral boat-docking feature has several useful applications.First, it provides a safe location for storing boats during stormsbecause the flexible nature of the nonwoven mesh island matrix providesan energy-absorbing support for the boat hull during periods of highwaves and/or wind. Second, the boat docking area provides an efficientmethod of supporting the boat during egress and ingress of passengerswho may be visiting the island for pleasure or maintenance. Third, theisland can be used to provide additional docking facilities whereexisting docking space is limited or expensive. Fourth, the island canbe used as a means for concealing a boat and passengers for hunting orwildlife photography purposes. Although the structure of FIG. 41 isshown surrounded by water, the structure could alternately be attachedto shore to act as a boat-docking pier.

FIG. 42 illustrates an anchoring device that can be used with thefloating island of the present invention. This figure is a top view ofan anchor 148 that is designed to hold a floating island regardless ofwind direction. The anchor 148 is comprised of four barbs 149 set at90-degree angles to each other and four ring attachment points 150, asshown. The anchor is designed to be secured to an island with fourtether lines (not shown) by attaching one end of each tether line toeach ring attachment point 150. The other end of each tether line issecured to an attachment point along the perimeter of an island. Eachbarb 149 is designed to catch and hold onto the pond bottom when thedirection of pull is opposite the direction of the point of the barb. Byhaving a plurality of barbs 149 facing in different directions, at leastone barb will be properly positioned for maximum holding abilityregardless of the direction pull.

Although numerous embodiments of the present invention have been shownand described, it will be apparent to those skilled in the art that manychanges and modifications may be made without departing from theinvention in its broader aspects. The appended claims are thereforeintended to cover all such changes and modifications as fall within thetrue spirit and scope of the invention.

REFERENCES

-   AUTEX Research Journal, Vol. 3, No. 2, Association of Universities    for Textiles, June 2003, p. 68.-   Joseph B. Franzini and E. John Finnemore, Fluid Mechanics, 9^(th)    ed., a McGraw-Hill Company, 1997.-   Robert Kadlee and Robert Knight, “Treatment Wetlands,” Lewis    Publishers, 1995.

1. A floating island comprising at least one layer of nonwoven meshmaterial, supplemental flotation units, stepping pads and one or moreartificial stepping stones.
 2. A floating island comprising a steppingstone flotation assembly, wherein the stepping stone flotation assemblycomprises at least two artificial stepping stones and a connecting cableunit.
 3. The floating island of claim 2, wherein the connecting cableunit is comprised of plastic rope.
 4. The floating island of claim 2,wherein the connecting cable unit is comprised of rustproof metal cable.5. A floating island comprising a stepping stone/vertical buoyant memberflotation assembly, wherein the stepping stone/vertical buoyant memberflotation assembly comprises an artificial stepping stone and avertically installed buoyant member.
 6. The floating island of claim 5,wherein the buoyant member is comprised of air-filled plastic pipe. 7.The floating island of claim 5, wherein the buoyant member is comprisedof closed cell foam-filled plastic pipe.